Champion petrol mower, cuts off after 10 miunts from start

[Zehroni]

my Champion primer 50 petrol mower start ok from clod then cuts off 10 or 15 minutes after use. I believe it cuts off when as soon as the engine gets hot. I have replaced the spark plug, engine oil, air filter, and cleaned the carburetor with high compressed air. I also put fresh petrol mixed with redux.

any ides why it cuts off please

 

[SammyInnit]

Do you use the choke? Thinking out loud.

 

[Zehroni]

yes I do to start with, but I put half way the speed scale soon after it fires up

 

[DaveHerns]

When it cuts out, is the spark plug wet or sooty?

 

[Mottie]

Is the air vent on the fuel tank clear?

 

[Burnerman]

Usually spark plug failure, but if you are running the machine flat out and then it fails, go for the fuel supply from the petrol tank.
John

 

[Zehroni]

When it cuts out, is the spark plug is neither wet or sooty, it is very hot
checked the air vent on the fuel tank and it is clear
I left the mower all day to call down and just start it now (evening), it stared straightway and I shut it off after few second, tries to start it again, it would not start despite the fact that the engine is called not hot. I am very puzzled.

 

[Burnerman]

Even though the machine is slightly warm, give it a whiff of choke and one pull on the starter. My guess is that it will fire up.
John

 

[Zehroni]

thank Johns, tried , it did not

 

[Burnerman]

Can you give me a picture of the carburettor and fuel tank please?
John

 

[Zehroni]

 

[Zehroni]

 

[Mottie]

Coil overheating?

 

[Burnerman]

You've definitely tried a brand new plug? I'd like to see a replacement igniter tried but they are generally very reliable.
John

 

[HERTS P&D]

Does the cap have a vent? After it cuts out remove the cap and try to start.

Andy